The Relationship between Self-Efficacy and Positive Thinking Ability in Adolescents at Karya Bhakti Middle School, Tarastar District, Humbang Hasundutan Regency, 2021 (Elisabeth Christina Tumanggor, Lindawati Simorangkir, & Amnita Ginting , Trans.). (2022). Jurnal Indah Sains Dan Klinis, 3(2), 50-56. https://doi.org/10.52622/jisk.v3i2.61